arm: add initial support for Amlogic Meson and ODROID-C2

This adds platform code for the Amlogic Meson GXBaby (S905) SoC and a
board definition for ODROID-C2. This initial submission only supports
UART and Ethernet (through the existing Designware driver). DTS files
are the ones submitted to Linux arm-soc for 4.7 [1].

[1] https://patchwork.ozlabs.org/patch/603583/

Signed-off-by: Beniamino Galvani <b.galvani@gmail.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
diff --git a/arch/arm/mach-meson/Kconfig b/arch/arm/mach-meson/Kconfig
new file mode 100644
index 0000000..77d3cfe
--- /dev/null
+++ b/arch/arm/mach-meson/Kconfig
@@ -0,0 +1,31 @@
+if ARCH_MESON
+
+config MESON_GXBB
+	bool "Support Meson GXBaby"
+	select ARM64
+	select DM
+	select DM_SERIAL
+	help
+	  The Amlogic Meson GXBaby (S905) is an ARM SoC with a
+	  quad-core Cortex-A53 CPU and a Mali-450 GPU.
+
+if MESON_GXBB
+
+config TARGET_ODROID_C2
+	bool "ODROID-C2"
+	help
+	  ODROID-C2 is a single board computer based on Meson GXBaby
+	  with 2 GiB of RAM, Gigabit Ethernet, HDMI, 4 USB, micro-SD
+	  slot, eMMC, IR receiver and a 40-pin GPIO header.
+
+endif
+
+config SYS_SOC
+	default "meson"
+
+config SYS_MALLOC_F_LEN
+	default 0x1000
+
+source "board/hardkernel/odroid-c2/Kconfig"
+
+endif
diff --git a/arch/arm/mach-meson/Makefile b/arch/arm/mach-meson/Makefile
new file mode 100644
index 0000000..44e3d63
--- /dev/null
+++ b/arch/arm/mach-meson/Makefile
@@ -0,0 +1,7 @@
+#
+# Copyright (c) 2016 Beniamino Galvani <b.galvani@gmail.com>
+#
+# SPDX-License-Identifier:	GPL-2.0+
+#
+
+obj-y += board.o
diff --git a/arch/arm/mach-meson/board.c b/arch/arm/mach-meson/board.c
new file mode 100644
index 0000000..782f86c
--- /dev/null
+++ b/arch/arm/mach-meson/board.c
@@ -0,0 +1,66 @@
+/*
+ * (C) Copyright 2016 Beniamino Galvani <b.galvani@gmail.com>
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#include <common.h>
+#include <libfdt.h>
+#include <linux/err.h>
+#include <asm/arch/gxbb.h>
+#include <asm/armv8/mmu.h>
+#include <asm/unaligned.h>
+
+DECLARE_GLOBAL_DATA_PTR;
+
+int dram_init(void)
+{
+	const fdt64_t *val;
+	int offset;
+	int len;
+
+	offset = fdt_path_offset(gd->fdt_blob, "/memory");
+	if (offset < 0)
+		return -EINVAL;
+
+	val = fdt_getprop(gd->fdt_blob, offset, "reg", &len);
+	if (len < sizeof(*val) * 2)
+		return -EINVAL;
+
+	/* Use unaligned access since cache is still disabled */
+	gd->ram_size = get_unaligned_be64(&val[1]);
+
+	return 0;
+}
+
+void dram_init_banksize(void)
+{
+	/* Reserve first 16 MiB of RAM for firmware */
+	gd->bd->bi_dram[0].start = CONFIG_SYS_SDRAM_BASE + (16 * 1024 * 1024);
+	gd->bd->bi_dram[0].size = gd->ram_size - (16 * 1024 * 1024);
+}
+
+void reset_cpu(ulong addr)
+{
+	psci_system_reset(true);
+}
+
+static struct mm_region gxbb_mem_map[] = {
+	{
+		.base = 0x0UL,
+		.size = 0x80000000UL,
+		.attrs = PTE_BLOCK_MEMTYPE(MT_NORMAL) |
+			 PTE_BLOCK_INNER_SHARE
+	}, {
+		.base = 0x80000000UL,
+		.size = 0x80000000UL,
+		.attrs = PTE_BLOCK_MEMTYPE(MT_DEVICE_NGNRNE) |
+			 PTE_BLOCK_NON_SHARE |
+			 PTE_BLOCK_PXN | PTE_BLOCK_UXN
+	}, {
+		/* List terminator */
+		0,
+	}
+};
+
+struct mm_region *mem_map = gxbb_mem_map;